228158172 has 72 divisors (see below), whose sum is σ = 643843200. Its totient is φ = 67525920.

The previous prime is 228158159. The next prime is 228158179. The reversal of 228158172 is 271851822.

228158172 is a `hidden beast` number, since 2 + 2 + 8 + 1 + 581 + 72 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228158179) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10329 + ... + 23727.

Almost surely, 2^228158172 is an apocalyptic number.

228158172 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 228158172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (321921600).

228158172 is an abundant number, since it is smaller than the sum of its proper divisors (415685028).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

228158172 is a wasteful number, since it uses less digits than its factorization.

228158172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13463 (or 13458 counting only the distinct ones).

The product of its digits is 17920, while the sum is 36.

The square root of 228158172 is about 15104.9055607773. The cubic root of 228158172 is about 611.0527123724.

The spelling of 228158172 in words is "two hundred twenty-eight million, one hundred fifty-eight thousand, one hundred seventy-two".